Flexible sensor with storage parameter information based on PET base material

Abstract

The utility model relates to a PET (polyethylene terephthalate) base material-based flexible sensor with stored parameter information, which comprises a flexible pressure sensor, a sensor interface and an FPC (flexible printed circuit) functional module, and the flexible pressure sensor comprises a PET flexible substrate and a pressure detection unit arranged on the PET flexible substrate. The FPC function module comprises an FPC flexible substrate, a storage unit and a temperature sensor unit, the storage unit and the temperature sensor unit are integrated on the flexible substrate, an FPC interface is arranged at the lower end of the FPC flexible substrate, and the FPC function module is electrically connected with an exposed bonding pad arranged on the flexible pressure sensor through the FPC interface, so that the FPC function module is integrated on the flexible pressure sensor. According to the utility model, the storage chip is integrated on the flexible sensor, and the sensor is endowed with an electronic identity card through the storage chip, so that design standardization, batch production and system calibration are facilitated in the production stage. And at a user side, the main control system can be matched with different flexible sensors, so that connection and play are realized, and returning to a factory for calibration or building of field calibration equipment is not needed.

Description

Technical Field

[0001] The utility model relates to the technical field of flexible sensors, in particular to a flexible sensor based on a PET substrate and having its own storage parameter information. Background Art

[0002] As a new type of sensor technology, flexible sensors are widely used in consumer electronics, medical equipment, smart homes, robots, and other fields due to their good flexibility, ductility, and even the ability to bend and fold freely, as well as their flexible and diverse structural forms. Compared with MEMS silicon-based sensors, flexible sensors currently have problems such as consistency errors, temperature drift, and static drift that are affected by the working environment due to the hysteresis effect. In addition, there are also phenomena such as sensor output signal attenuation as the service life increases.

[0003] In view of the above problems, the current solution is to calibrate the product and store the calibration parameters in the main control chip of the back-end control board. However, there are some problems to be solved in this method:

[0004] 1. Users often do not have the conditions for accurate calibration and need to return to the manufacturer for calibration.

[0005] 2. The sensor cannot be replaced arbitrarily, and recalibration is required every time the sensor is replaced.

[0006] 3. Sensor calibration parameters need to be delivered in electronic document form. There are data security risks through email, CD, USB flash drive, etc. Utility Model Content

[0007] The technical problem solved by the utility model is to provide a flexible sensor based on a PET substrate and having its own storage parameter information.

[0008] The technical solution adopted by the utility model to solve its technical problems is:

[0009] A flexible sensor with self-storage parameter information based on a PET substrate, comprising a flexible pressure sensor designed based on the PET substrate, a sensor interface and an FPC functional module, wherein the sensor interface is arranged at the front end of the flexible pressure sensor, the flexible pressure sensor comprises a PET flexible substrate and a pressure detection unit arranged on the PET flexible substrate, the FPC functional module comprises an FPC flexible substrate, and a storage unit and a temperature sensor unit integrated on the flexible substrate, the FPC interface is arranged at the lower end of the FPC flexible substrate, the flexible pressure sensor is provided with an exposed solder pad that matches the FPC interface, and the FPC functional module is connected to the flexible pressure sensor through the FPC interface. The exposed pad is electrically connected to the flexible pressure sensor, thereby integrating the FPC functional module on the flexible pressure sensor; the storage unit includes a storage chip for storing production information, calibration information and usage information of the flexible pressure sensor, the temperature sensor unit includes a temperature sensor for measuring the temperature of the flexible sensor when it is working, the pressure detection unit, the storage unit and the temperature sensor unit are electrically connected to the sensor interface through the lead rules set on the flexible pressure sensor, and are electrically connected to the external main control system through the sensor interface, so as to provide the required working voltage for the pressure detection unit, the storage unit and the temperature sensor unit, and perform data transmission and communication.

[0010] Furthermore, the flexible pressure sensor includes a PET lower flexible substrate, a PET upper flexible substrate and the pressure detection unit arranged between the upper and lower flexible substrates, the PET lower flexible substrate and the PET upper flexible substrate are connected together by an elastic supporting layer, and the pressure detection unit is arranged inside the elastic supporting layer and surrounded by the elastic supporting layer; the pressure detection unit includes an electrode layer and a sensing layer, the electrode layer and the sensing layer are respectively arranged on the upper and lower flexible substrates, and are led out to the sensor interface through leads arranged on the upper and lower flexible substrates.

[0011] Furthermore, the elastic support layer adopts a rectangular structure, a C-shaped structure or a strip structure, and the elastic support layer connects the PET upper flexible substrate and the PET lower flexible substrate and supports and separates them.

[0012] Furthermore, a plurality of micro elastic protrusion structures are arranged between the upper and lower flexible substrates.

[0013] Preferably, the plurality of micro elastic protrusion structures are spherical protrusions or strip-shaped protrusions.

[0014] Furthermore, the FPC functional module is arranged at a location close to the sensor interface, and the storage unit and the temperature sensor unit integrated thereon are provided with a protective glue layer through glue dispensing.

[0015] Furthermore, a protective layer is provided on the flexible pressure sensor through a packaging layer, and the packaging layer and the protective layer wrap the pressure detection unit, the storage unit and the temperature sensor unit for protection, and only the PET leaves the sensor interface to be electrically connected to the main control system.

[0016] The beneficial effects of the utility model are:

[0017] 1. Compared with the current common way of implementing sensor signal processing through back-end processing circuits, the utility model creates an integrated circuit chip or circuit module with data storage function pre-integrated into the flexible sensor, which can store the production information, calibration information, and working information of the sensor, and can realize modular design and production of sensors and main control circuits, making it convenient for users to replace the required sensor models at any time.

[0018] 2. By integrating the storage chip into the flexible sensor, the characteristic parameters of the sensor can be stored in the storage chip, which can give the sensor an "electronic ID card", which is conducive to the design of standardized, batch production and calibration systems in the production stage, and realizes the large-scale production of sensors. On the user side, the main control system can match different flexible sensors, and realize immediate use without the need to return to the factory for calibration or set up on-site calibration equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of the utility model;

[0020] Figure 2 It is an explosion state diagram of an embodiment of the utility model;

[0021] Figure 3 for Figure 2 The combined state diagram of

[0022] Figure 4 It is the system principle diagram of the utility model;

[0023] Figure 5 This is a temperature correction comparison diagram of the utility model;

[0024] Figure 6 This is a comparison diagram of attenuation correction of the utility model;

[0025] in:

[0026] 1. Flexible pressure sensor, 2. Storage unit, 3. Temperature sensor unit, 4. Sensor interface, 5. FPC functional module;

[0027] 101. pressure detection unit, 102. soldering pad, 11. PET lower flexible substrate, 12. elastic supporting layer, 13. PET upper flexible substrate, 14. encapsulation layer, 15. protective layer. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0030] like Figure 1-4 As shown, the utility model provides a flexible sensor with self-storage parameter information based on a PET substrate, including a flexible pressure sensor 1 designed based on a PET substrate, and a storage unit 2 and a temperature sensor unit 3 are integrated on the flexible pressure sensor 1. The storage unit 2 is used to store the production, calibration and use information of the flexible sensor, including a storage chip. The temperature sensor 3 unit is used to measure the ambient temperature when the flexible sensor is working, including a temperature sensor.

[0031] Among them, the flexible pressure sensor adopts a capacitive, resistive or piezoelectric flexible pressure sensor or an array flexible pressure sensor, and the substrate of the flexible pressure sensor adopts a flexible substrate of PI substrate.

[0032] Among them, the storage chip adopts EEPROM (Electrically Erasable Programmable Read-Only Memory), FLASH (Flash Memory Chip), RFID chip, etc. The data content stored in the storage chip includes: production information, calibration information, usage information, etc.

[0033] Production information includes: sensor serial number, production batch, serial number, production date, manufacturer, workshop, production line and other information.

[0034] The calibration information includes: the factory calibration parameters of the sensor (including but not limited to the environment configured during calibration, matching detection circuit parameters, the corresponding relationship between pressure and sensor output signal, characteristic curve fitting parameters, etc.).

[0035] Usage information includes: number of times the sensor is used, duration, product quality status, etc.

[0036] The temperature sensor uses a temperature sensor based on the NTC or PTC principle. The packaging form is not limited, and the SMD chip type is preferred.

[0037] Furthermore, the utility model of a flexible pressure sensor with self-storage parameter information based on PI substrate also includes a sensor interface 4, which includes a communication interface, a power supply interface and a data interface. Among them, the communication interface is used for communication and data transmission between the memory chip and the temperature sensor, and the communication interface adopts a wired interface such as IIC, SPI, CAN, 485, 232, TTL, or a wireless form such as RFID.

[0038] Embodiment 1:

[0039] like Figure 1-3 As shown, it is a specific structural diagram of the flexible sensor with self-storage parameter information based on PET substrate of the utility model, including a flexible pressure sensor 1 designed based on PET substrate, and the sensor interface is arranged at the front end of the flexible pressure sensor 1. The storage unit 2 and the temperature sensor unit 3 are regularly arranged and welded on another flexible substrate to form an independent FPC functional module 5, and the substrate of the FPC functional module 5 can adopt a PI flexible substrate. The lower end of the FPC functional module 5 is provided with an FPC interface, and the FPC interface is designed as an exposed pad. At the same time, the detection circuit on the flexible pressure sensor 1 is designed with an exposed pad 102 that matches the FPC interface, and is electrically connected to the sensor interface 4 through the lead wires arranged on the flexible pressure sensor 1.

[0040] The exposed pads on the FPC functional module 5 and the flexible pressure sensor 1 are assembled together using a conductive adhesive hot pressing process, thereby enabling the signals of the storage unit and the temperature sensor unit to communicate with the outside through the circuit on the flexible pressure sensor and the flexible sensor circuit.

[0041] The storage chip, temperature sensor and related electronic components in the storage unit and the temperature sensor unit are directly soldered to the corresponding pads of the PI flexible substrate through the SMT process to form the FPC functional module 5 in this embodiment.

[0042] Further, such as Figure 2As shown, the flexible pressure sensor 1 includes a PET lower flexible substrate 11, a PET upper flexible substrate 13 is arranged on the PET lower flexible substrate 11 through an elastic supporting layer 12, and an electrode layer and a sensing layer are respectively arranged on the upper surface of the PET lower flexible substrate 11 and the lower surface of the PET upper flexible substrate 13 to form a pressure detection unit 101. The pressure detection unit 101 is arranged inside the elastic supporting layer 12 and wrapped by the elastic supporting layer 12.

[0043] The electrode layer and the sensing layer can be arranged in reverse, that is, the sensing layer is arranged on the PET lower flexible substrate, and the electrode layer is arranged on the PET upper flexible substrate.

[0044] The specific materials of the electrode layer and the sensor layer are not limited, and can be:

[0045] 1. When both the electrode layer and the sensing layer are made of conductor materials with low impedance, the principle of pressure detection is to increase or decrease the contact area between the electrode layer and the sensing layer to change the contact resistance, thereby achieving pressure detection. Conductor materials include but are not limited to silver, conductive polymer materials, conductive nanowires, inorganic conductive materials (carbon-based materials), etc.

[0046] 2. When the electrode layer is made of a conductor material with low impedance and the sensing layer is made of a semiconductor material with sensor function, the pressure detection principle is to achieve pressure detection through the piezoresistive effect of the semiconductor material with sensor function. Semiconductor materials include but are not limited to carbon nanocomposites.

[0047] Furthermore, the specific structure of the elastic support layer 12 is not limited, including but not limited to a rectangular, C-shaped or strip structure. Figure 2 As described in the above, a rectangular structure is adopted to wrap and seal the pressure detection unit 101 inside the PET lower flexible substrate 11 and the PET upper flexible substrate 13. A C-row structure can also be adopted to wrap the pressure detection unit, leaving a right opening. Alternatively, a strip shape is adopted, which is arranged on the upper and lower sides of the PET lower flexible substrate and the PET upper flexible substrate, leaving a left opening and a right opening between the lower flexible substrate and the upper flexible substrate.

[0048] Furthermore, a number of micro elastic protrusion structures are provided between the upper and lower flexible substrates. The elastic protrusion structures are spherical protrusions or strip protrusions. The elasticity between the upper and lower flexible substrates can be increased through the elastic protrusion structures, thereby increasing the sensitivity of the flexible pressure sensor.

[0049] Furthermore, in this embodiment, the FPC functional module 5 provided with the storage unit 2 and the temperature sensor unit 3 is arranged close to the sensor interface 4, and the circuit on the FPC functional module is protected by a glue dispensing process, thereby improving the reliability of the flexible sensor.

[0050] Embodiment 2:

[0051] like Figure 2-3 As shown, further, based on Example 1, a protective layer 15 is provided on the upper end of the flexible pressure sensor 1 through a packaging layer 14, and the packaging layer and the protective layer wrap the sensor detection unit 101 and the FPC functional module 5 for protection, leaving only the sensor interface 4 for electrical connection with the external main control system.

[0052] The material of the protective layer 15 is not limited, and a PET substrate is preferably selected as the protective layer.

[0053] It can be seen from the embodiments that compared with the current common method of realizing sensor signal processing through back-end processing circuits, the utility model creates an integrated circuit chip or circuit module with data storage function that is pre-integrated into the flexible sensor, which can store the production information, calibration information, and working information of the sensor, and can realize modular design and production of sensors and main control circuits, making it convenient for users to replace the required sensor models at any time.

[0054] In view of the temperature drift characteristics of flexible sensors, a temperature sensor is integrated on the flexible sensor to monitor the working temperature of the sensor in real time. According to the temperature drift coefficient of the sensor, the output signal of the sensor is compensated and calculated in advance at the sensor end, thereby improving the signal consistency of the sensor in different working environments. Then, the static drift error of the sensor is reduced through an algorithm, and the static drift curve of the sensor is stored in the sensor. After starting work, the output signal is compensated according to the working time of the sensor, thereby reducing the static working error of the sensor, realizing self-compensation at the sensor end, and improving the convenience of sensor use.

[0055] For this reason, Figure 5 The figure below is a temperature correction comparison chart for sensor temperature drift performance calibration. During the sensor R&D and testing phase, the temperature drift performance of the sensor is measured, that is, the percentage change in the sensor output signal as the working environment temperature changes under the same input physical quantity conditions. This parameter is written into the storage chip on the flexible sensor. When the main control system is working, it is first read out, and then the correction coefficient is compensated to the calculated pressure value according to the measured ambient temperature. The output signal of the corrected curve sensor will not change with temperature.

[0056] The specific correction formula is as follows:

[0057] According to the following function, the measured operating temperature and sensor output signal are used to calculate the external physical quantity:

[0058] y=f 25℃ (x)×G(temp)

[0059] in:

[0060] G(temp) is the drift function of the sensor, which is the ratio of the sensor output signal under the current working temperature condition to the working condition of 25℃:

[0061]

[0062] In the above formula:

[0063] S out(temp) It is the output signal value of the sensor under the current working temperature condition;

[0064] S out(25℃) It is the output signal value of the sensor under the working condition of 25℃;

[0065] f 25℃ It is the functional relationship between the external physical quantity and the sensor output signal at 25°C.

[0066] like Figure 6 The figure shows the comparison of sensor signal attenuation correction. During the sensor R&D and testing phase, the attenuation performance of the sensor is measured. That is, under the same input physical quantity conditions, as the sensor working time / number of times increases, the attenuation of the sensor output signal. This parameter is written into the storage integrated circuit on the flexible sensor. When the main control system is working, it is read out first, and then the correction coefficient is compensated to the calculated pressure value according to the sensor's working history. The corrected pressure value will be stabilized within the ±3% error range.

[0067] According to the following function, the sensor working time data and sensor output signal stored on the chip are read to calculate the external physical quantity:

[0068] y=f T0 (x)×G(t)

[0069] in:

[0070] G(t) is the attenuation function of the sensor, which is the ratio of the sensor output signal under the current working time condition to the initial T0 working condition:

[0071]

[0072] f T0 It is the functional relationship between the external physical quantity of the sensor and the output signal of the sensor under the initial working condition of T0.

[0073] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A flexible sensor based on PET substrate with built-in storage parameter information, characterized in that: The invention comprises a flexible pressure sensor designed based on a PET substrate, a sensor interface and an FPC functional module, wherein the sensor interface is arranged at the front end of the flexible pressure sensor, the flexible pressure sensor comprises a PET flexible substrate and a pressure detection unit arranged on the PET flexible substrate, the FPC functional module comprises an FPC flexible substrate, and a storage unit and a temperature sensor unit integrated on the flexible substrate, an FPC interface is arranged at the lower end of the FPC flexible substrate, an exposed pad matching the FPC interface is arranged on the flexible pressure sensor, and the FPC functional module is electrically connected to the exposed pad arranged on the flexible pressure sensor through the FPC interface, thereby The FPC functional module is integrated on the flexible pressure sensor; the storage unit includes a storage chip for storing production information, calibration information and usage information of the flexible pressure sensor, the temperature sensor unit includes a temperature sensor for measuring the temperature of the flexible sensor when it is working, the pressure detection unit, the storage unit and the temperature sensor unit are electrically connected to the sensor interface through the lead rules set on the flexible pressure sensor, and are electrically connected to the external main control system through the sensor interface, so as to provide the required working voltage for the pressure detection unit, the storage unit and the temperature sensor unit, and perform data transmission and communication.

2. A flexible sensor based on a PET substrate and having its own storage parameter information as claimed in claim 1, characterized in that: The flexible pressure sensor includes a PET lower flexible substrate, a PET upper flexible substrate and the pressure detection unit arranged between the upper and lower flexible substrates, the PET lower flexible substrate and the PET upper flexible substrate are connected together by an elastic supporting layer, and the pressure detection unit is arranged inside the elastic supporting layer and surrounded by the elastic supporting layer; the pressure detection unit includes an electrode layer and a sensing layer, the electrode layer and the sensing layer are respectively arranged on the upper and lower flexible substrates, and are led out to the sensor interface through leads arranged on the upper and lower flexible substrates.

3. A flexible sensor based on a PET substrate and having its own storage parameter information as claimed in claim 2, characterized in that: The elastic support layer adopts a rectangular structure, a C-shaped structure or a strip structure, and the elastic support layer connects the PET upper flexible substrate and the PET lower flexible substrate and supports and separates them.

4. A flexible sensor based on a PET substrate and having its own storage parameter information as claimed in claim 3, characterized in that: A plurality of micro elastic protrusion structures are also arranged between the upper and lower flexible substrates.

5. A flexible sensor based on a PET substrate and having its own storage parameter information as claimed in claim 4, characterized in that: The plurality of micro elastic protrusion structures are spherical protrusions or strip-shaped protrusions.

6. A flexible sensor based on a PET substrate and having its own storage parameter information as claimed in any one of claims 1 to 5, characterized in that: The FPC functional module is arranged at a location close to the sensor interface, and the storage unit and the temperature sensor unit integrated thereon are provided with a protective glue layer through glue dispensing.

7. A flexible sensor based on a PET substrate and having its own storage parameter information as claimed in claim 6, characterized in that: A protective layer is also provided on the flexible pressure sensor through a packaging layer, and the packaging layer and the protective layer wrap the pressure detection unit, the storage unit and the temperature sensor unit for protection, leaving only the sensor interface for electrical connection with the main control system.

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